[Amended] Supply contract signed

What happened

IS Dongseo / Supply Contract Signed / (2026.08.31) Supply Contract Signed

Amendment Report Amendment date: 2026-08-31

1. Disclosure document being amended: Single Sale/Supply Contract Signed 2. Filing date of the disclosure document being amended: 2026-07-29 3. Reason for amendment: Amendment due to the conclusion of a change-order contract

4. Amended items Item 2. Contract details - Contract amount (KRW): Before: 450,208,827,000; After: 480,312,687,000 Item 2. Contract details - As a percentage of revenue (%): Before: 46.7; After: 49.82 Item 6. Key contract terms - Payment terms, etc.: Before: Payment upon unit presale; After: -

- Single Sale/Supply Contract Signed

1. Type of sale/supply contract: Construction order received Contract name: Nam-gu B-14 District Housing Redevelopment Project

2. Contract details Contract amount (KRW): 480,312,687,000 Most recent revenue (KRW): 964,111,879,557 As a percentage of revenue (%): 49.82 Whether a large corporation: Applicable

3. Counterparty: Nam-gu B-14 District Housing Redevelopment Project Association Relationship with the Company: -

4. Sale/supply region: Around 350-5 Yaeum-dong, Nam-gu, Ulsan Metropolitan City

5. Contract period Start date: 2026-08-01 End date: 2029-10-31

6. Key contract terms Whether there is a contract deposit/advance payment: No Payment terms, etc.: Payment upon unit presale

7. Contract (order) date: 2020-09-24

8. Matters relating to disclosure deferral Reason for deferral: - Deferral deadline: -

9. Other important matters relevant to investment decisions - Item 2, the contract amount (KRW), above excludes value-added tax. - Item 2, the most recent revenue (KRW), above is based on the consolidated financial statements as of the end of 2019. - Item 5, the contract period, above is the construction period, being 39 months from the actual commencement date. - Item 7, the contract (order) date, above is the date the construction contract was executed. - The contract period, contract amount, etc. may change depending on how the project proceeds or on conditions stipulated in the construction contract.

* Project overview 2 basement floors / 30 floors above ground, 13 apartment buildings, 1,521 households, plus ancillary welfare facilities

* Related disclosures 2026-07-29 Single Sale/Supply Contract Signed 2025-02-14 Single Sale/Supply Contract Signed 2020-09-24 Single Sale/Supply Contract Signed